G.3 Running Octave From Within Emacs

The package ‘octave’ provides commands for running an inferior
Octave process in a special Emacs buffer. Use

M-x run-octave

to directly start an inferior Octave process. If Emacs does not know
about this command, add the line

(autoload 'run-octave "octave-inf" nil t)

to your ‘.emacs’ file.

This will start Octave in a special buffer the name of which is
specified by the variable inferior-octave-buffer and defaults to
"*Inferior Octave*". From within this buffer, you can
interact with the inferior Octave process `as usual', i.e., by entering
Octave commands at the prompt. The buffer is in Inferior Octave mode,
which is derived from the standard Comint mode, a major mode for
interacting with an inferior interpreter. See the documentation for
comint-mode for more details, and use C-h b to find out
about available special keybindings.

You can also communicate with an inferior Octave process from within
files with Octave code (i.e., buffers in Octave mode), using the
following commands.

C-c i l

Send the current line to the inferior Octave process
(octave-send-line).
With positive prefix argument N, send that many lines.
If octave-send-line-auto-forward is non-nil, go to the
next unsent code line.

C-c i b

Send the current block to the inferior Octave process
(octave-send-block).

C-c i f

Send the current function to the inferior Octave process
(octave-send-defun).

C-c i r

Send the region to the inferior Octave process
(octave-send-region).

C-c i s

Make sure that `inferior-octave-buffer' is displayed
(octave-show-process-buffer).

C-c i h

Delete all windows that display the inferior Octave buffer
(octave-hide-process-buffer).

C-c i k

Kill the inferior Octave process and its buffer
(octave-kill-process).

The effect of the commands which send code to the Octave process can be
customized by the following variables.

octave-send-echo-input

Non-nil means echo input sent to the inferior Octave process.
Default is t.

octave-send-show-buffer

Non-nil means display the buffer running the Octave process after
sending a command (but without selecting it).
Default is t.

If you send code and there is no inferior Octave process yet, it will be
started automatically.

The startup of the inferior Octave process is highly customizable.
The variable inferior-octave-startup-args can be used for
specifying command lines arguments to be passed to Octave on startup
as a list of strings. For example, to suppress the startup message and
use `traditional' mode, set this to '("-q" "--traditional").
You can also specify a startup file of Octave commands to be loaded on
startup; note that these commands will not produce any visible output
in the process buffer. Which file to use is controlled by the variable
inferior-octave-startup-file. If this is nil, the file
‘~/.emacs-octave’ is used if it exists.

And finally, inferior-octave-mode-hook is run after starting the
process and putting its buffer into Inferior Octave mode. Hence, if you
like the up and down arrow keys to behave in the interaction buffer as
in the shell, and you want this buffer to use nice colors, add

to your ‘.emacs’ file. You could also swap the roles of C-a
(beginning-of-line) and C-c C-a (comint-bol) using
this hook.

Note that if you set your Octave prompts to something different
from the defaults, make sure that inferior-octave-prompt matches
them. Otherwise, nothing will work, because Emacs will not know
when Octave is waiting for input, or done sending output.